Greg Isenberg calls now the best time for startup arbitrage

GREG ISENBERG @gregisenbergOriginally posted 2026.09.23

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I find it fascinating how many people think this is a bad time to start a company. Grok 4.7, GPT-6 Sol/Luna, Opus 5.5, Astra, Gemini 3.8 Live, Muse, Instinct, Jev, Agent APIs etc. That's the last 3 weeks (crazy progress on personal agents/voice AI). Because arbitrage means the same thing trades at 2 prices in 2 markets (and it's your wedge). And usually you have to hunt for those gaps, because they're rare and they close the moment anyone notices. What's different now is that they're opening faster than anyone can build into them! I think this has got to be the greatest time for arbitrage in history.